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Tilapiametric
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Transcript of Tilapiametric
TILAPIA CULTUREby
Leonard LovshinDepartment of Fisheries and Allied Aquacultures
Auburn University, AL 36849 U.S.A.
Water Temperatures for:
Tilapia are native to Africa, Israel and Jordan
Best growth- above 250CSpawning - above 200C
Death- 10 to 120C
Nile Tilapia Mozambique Tilapia
Blue Tilapia Red Tilapia
Popular Cultured TilapiasPopular Cultured Tilapias
Food HabitsTilapia feed low on the food chain
phytoplankton
zooplankton
Tilapia can be cultured in fresh and salt water. 1. All tilapia can be grown in fresh water.
2. Mossambique tilapia and red tilapia with Mossambique tilapia genes can be grown in salt water.
Reproduction
Males dig and defend a nest
Females incubate eggs
and defend the fry
Tilapia can be spawned in:
1. ponds
2. cages ( hapas )
3. tanks
Fry can be harvested:
2. 40 days after stocking brood fish
1. 18 days after stocking brood fish
Fry can be:1. partial harvested
2. completely harvested
Eggs can be removed from females:
Incubating tilapia eggs
Yolk-sac tilapia fry
Tilapia can be cultured as:
1. Mixed sexes - males and females together
2. Mono-sex - only males
Advantages: 1. Technically easy
Disadvantages: 1. Small harvest weight 2. Mixed sizes at harvest
Grow-out:
Mixed-sex Culture
Advantages: 1. Large harvest weight 2. Uniform size at harvest
Disadvantages: 1. Technically difficult
Mono-sex culture
Stocking a predacious fish with mixed-sex tilapiawill control tilapia density and increase final harvest weight.
Largemouth bass in the U. S. A.
Peacock bass inSouth America
Mono-sex male tilapia populations can be produced by:
1. Visual selection
2. Hybridization
3. Sex-reversal
4. Genetic manipulation
Male Populations
Visual Selection of the Genital Papilla
Male papilla
Female papilla withoviduct
anus
anus
Hybridization
Male Hornorum tilapia
Female Nile tilapia All-male hybrid tilapia
ZZ
XX
XZ
Sex Reversal of Tilapia Fry
Genetic Manipulation
1) XXF + XYM
estrogen
XXF + XY”F”
2) XY”F” x XYM
XXF + 2 XYM + YYM
3) XXF x YYM
100% XYM
Tilapia are raised in:
Small earthen ponds
Tilapia are raised in:Large earthen ponds
Harvested tilapia are held in net enclosures while waiting to be loaded onto trucks for transport to processors.
Tilapia are raised in:Floating cages
Tilapia are raised in:Circular tanks with partial water exchange and mechanical aeration
Tilapia are raised in:Raceways with constant water exchange
Tilapia are raised in:Indoors with water reuse, mechanical aeration and oxygen injection
Tilapia ponds can be fertilized with organic and inorganic fertilizers to increase yield
Tilapia can be fed to increase yield
Tilapia can be fedAgricultural by-products Pelleted feeds
sinking
floating
cottonseed meal wheat bran
rice bran
Tilapia can be sold to
Neighbors and
Friends
Tilapia can be purchasedAt supermarkets and fish shops
whole on ice
fresh and frozen fillets
1. Most production is from enclosed, water reuse systems because of cold winter water temperatures.
2. Production costs are high.
3. Most tilapia are sold live or whole iced.
4. Presently, U. S. producers can’t compete with producers in tropical climates for processed tilapia.
5. Fresh fillets are imported from Central and South America.
6. Frozen whole tilapia and fillets are imported from Asia.
Tilapia farming in the U. S.
1. feeds low on the food chain
2. accepts wide range of feeds
3. resistant to poor water quality, disease and handling
4. good flesh quality
5. fingerlings easy to produce year round
Advantages of Farming Tilapia
1. sensitive to low water temperatures
2. reach sexual maturity at a young age
3. males grow faster than females
4. difficult to harvest from earthen ponds with a seine
5. low dressout percentage of fillet
Disadvantages of raising tilapia
Over 2.0 million mt of farmed tilapia were harvest world-wide in 2004.
China>Egypt>Indonesia
U. S. tilapia Production 2004: 9,000 MT
EAT MORE TILAPIA